Usefulness of biomarkers to predict prognosis after heart transplant

INTRODUCTION AND OBJECTIVES

Heart transplant (HT) represents a major physiological stress, resulting in elevated levels of analytical biomarkers. This study aimed to determine whether changes in biomarker levels after HT can identify patients with a poor prognosis.

METHODS

A prospective longitudinal noninterventional study was conducted in 149 consecutive patients undergoing HT from July 2017 to July 2023. Biomarkers were assessed before HT and at 6, 24, 48, 72, and 96hours after HT. The biomarkers analyzed were high-sensitivity troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), creatinine, and lactic acid. The primary outcome was a composite of death and severe primary graft failure (PGF).

RESULTS

NT-proBNP and troponin levels remained highly elevated throughout the period and stabilized from the first 24hours post-HT. Lactate levels stabilized after the first 24hours, and creatinine from the second day onward. Exitus occurred in 23 (15%) of the patients, and severe PGF in 26 (17%). All biomarkers were significantly associated with the incidence of the combined event (P <.0001). Receiver operating characteristic curve analysis at 24hours showed significant areas under the curve (P=.0001). The greatest discriminatory power was observed for the NT-proBNP curve. A value of 10 000 pg/mL had a sensitivity of 90% and specificity of 80%.

CONCLUSIONS

A significant elevation of post-HT analytical biomarkers was associated with mortality and/or severe PGF. Among the biomarkers analyzed, NT-proBNP was the most accurate in classifying patients.

Urinary N-Terminal Pro-Brain Natriuretic Peptide Predicts Acute Kidney Injury and Severe Disease in COVID-19

INTRODUCTION

The ongoing COVID-19 pandemic is placing an extraordinary burden on our health care system with its limited resources. Accurate triage of patients is necessary to ensure medical care for those most severely affected. In this regard, biomarkers could contribute to risk evaluation. The aim of this prospective observational clinical study was to assess the relationship between urinary N-terminal pro-brain natriuretic peptide (NT-proBNP) and acute kidney injury (AKI) as well as severe disease in patients with COVID-19.

METHODS

125 patients treated with an acute respiratory infection in the emergency department of the University Hospital Regensburg were analyzed. These patients were divided into a COVID-19 cohort (n = 91) and a cohort with infections not caused by severe acute respiratory syndrome-coronavirus-2 (n = 34). NT-proBNP was determined from serum and fresh urine samples collected in the emergency department. Clinical endpoints were the development of AKI and a composite one consisting of AKI, intensive care unit admission, and in-hospital death.

RESULTS

11 (12.1%) COVID-19 patients developed AKI during hospitalization, whereas 15 (16.5%) reached the composite endpoint. Urinary NT-proBNP was significantly elevated in COVID-19 patients who suffered AKI or reached the composite endpoint (each p < 0.005). In a multivariate regression analysis adjusted for age, chronic kidney disease, chronic heart failure, and arterial hypertension, urinary NT-proBNP was identified as independent predictor of AKI (p = 0.017, OR = 3.91 [CI: 1.28-11.97] per standard deviation [SD]), as well as of the composite endpoint (p = 0.026, OR 2.66 [CI: 1.13-6.28] per SD).

CONCLUSION

Urinary NT-proBNP might help identify patients at risk for AKI and severe disease progression in COVID-19.

Use of Urine N-Terminal Prohormone of Brain-Natriuretic Peptide (NT-proBNP) as a Non-Invasive Indicator for Renal Function Recovery after Surgical Relief of Hydronephrosis

Cardiorenal syndrome is rarely discussed in patients with obstructive uropathy. On the other hand, there is currently no accurate and convenient clinical biomarker to predict the recovery of renal function after the resolution of ureteral obstruction. The purpose of this study is to explore the association between hydronephrosis and cardiorenal syndrome by measuring the change of the N-terminal prohormone of brain-natriuretic peptide (NT-proBNP), which is a biomarker typically used for cardiac failure, in patients receiving surgery to relieve obstructive uropathy. A total of 212 patients admitted for ureteroscopic (URS) procedures to relieve hydronephrosis were enrolled in this study. The severity of hydronephrosis as well as plasma and urine NT-proBNP levels were obtained before and after surgery. The results showed a significant correlation between urine NT-proBNP levels and renal function recovery following the resolution of hydronephrosis (OR 3.24, 95% CI 1.09−9.70, p = 0.035). Urine NT-proBNP could even predict the recovery of renal function with an area under the ROC = 0.775 (0.65−0.88, p < 0.001). In conclusion, urine NT-proBNP could be a useful early marker of renal function recovery after URS surgery, identifying patients whose renal and heart functions were compromised by the obstruction.

Urine N-terminal pro-B-type natriuretic peptide and plasma proenkephalin are promising biomarkers for early diagnosis of cardiorenal syndrome type 1 in acute decompensated heart failure: a prospective, double-center, observational study in real-world

Background

Patients with acute decompensated heart failure (ADHF) show cardiorenal syndrome type 1 (CRS-1) are more likely to have a poor outcome. However, the current criteria often lead to delayed CRS-1 diagnosis. Therefore, we evaluated the predictive value of plasma proenkephalin (pPENK) and urine NT-proBNP (uNT-proBNP) for early diagnosis of CRS-1 and vulnerable-phase prognosis in ADHF patients.

Methods

The plasma NT-proBNP (pNT-proBNP), pPENK, and uNT-proBNP were measured in 121 ADHF patients on admission. The plasma neutrophil gelatinase-associated lipocalin (pNGAL) was chosen as the reference. Logistic regression was used to determine the predictors of CRS-1. The area under the receiver operating curves (ROCs) was calculated to assess the early diagnostic value of pNGAL, pPENK, and uNT-proBNP/uCr for CRS-1. To evaluate the prognostic risk of factors for the 90-d outcomes of all ADHF patients, the Cox regression was performed and the cumulative risk curve was plotted.

Results

We found that pPENK [OR 1.093 (95% CI 1.022–1.169), p = 0.010; AUROC = 0.899 (95% CI 0.831–0.946)] and uNT-proBNP/uCr ratio [OR 1.015 (95% CI 1.003–1.028), p = 0.012; AUROC = 0.934 (95% CI 0.874–0.971)] could independently predict the occurrence of CRS-1 in hospitalized patients with ADHF. The pPENK [HR 1.014 (95% CI 1.000–1.042), p = 0.044] and uNT-proBNP/uCr ration [HR 0.998 (95% CI 0.997–1.000), p = 0.045] were also independent predictors of the risk of HF readmission or all-cause death 90 d after discharge in ADHF patients.

Conclusions

The newly found pPENK and noninvasive test of uNT-proBNP/uCr ratio (pg/nmol) on admission may be two promising novel predictive biomarkers for early diagnosis of CRS-1 occurrence and vulnerable-phase outcomes in ADHF patients.

B-Type Natriuretic Peptide at Admission Is a Predictor of All-Cause Mortality at One Year after the First Acute Episode of New-Onset Heart Failure with Preserved Ejection Fraction

Background: Heart failure with preserved ejection fraction (HFpEF) has been assessed extensively, but few studies analysed the predictive value of the NT-proBNP in patients with de novo and acute HFpEF. We sought to identify NT-proBNP at admission as a predictor for all-cause mortality and rehospitalisation at 12 months in patients with new-onset HFpEF. Methods: We analysed 91 patients (73 ± 11 years, 68% females) admitted for de novo and acute HFpEF, using the Cox proportional hazard risk model. Results: An admission NT-proBNP level above the threshold of 2910 pg/mL identified increased all-cause mortality at 12 months (AUC = 0.72, sensitivity = 92%, specificity = 53%, p < 0.001). All-cause mortality adjusted for age, gender, medical history, and medication in the augmented NT-proBNP group was 16-fold higher (p = 0.018), but with no difference in rehospitalisation rates (p = 0.391). The predictors of increased NT-proBNP ≥ 2910 pg/mL were: age (p = 0.016), estimated glomerular filtration rate (p = 0.006), left atrial volume index (p = 0.001), history of atrial fibrillation (p = 0.006), and TAPSE (p = 0.009). Conclusions: NT-proBNP above 2910 pg/mL at admission for de novo and acute HFpEF predicted a 16-fold increased mortality at 12 months, whereas values less than 2910 pg/mL forecast a high likelihood of survival (99.3%) in the next 12 months, and should be considered as a useful prognostic tool, in addition to its utility in diagnosing heart failure.

Plasmatic Dimethylarginines in Dogs With Myxomatous Mitral Valve Disease

Plasmatic dimethylarginines, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) are considered biomarkers of endothelial and renal dysfunction, respectively, in humans. We hypothesize that plasmatic concentration of dimethylarginines in dogs with myxomatous mitral valve disease (MMVD) is influenced by heart disease stage. Eighty-five client-owned dogs with MMVD, including 39, 19, and 27 dogs in ACVIM stages B1, B2, and C+D, respectively, and a control group of 11 clinically healthy dogs were enrolled. A prospective, multicentric, case-control study was performed. Each dog underwent a complete clinical examination, arterial blood pressure measurement, thoracic radiography, six-lead standard electrocardiogram, transthoracic echocardiography, CBC, biochemical profile, and urinalysis. Plasmatic concentration of dimethylarginines was determined through high-performance liquid chromatography coupled with tandem mass spectrometry. Median ADMA was significantly increased in dogs of group C+D (2.5 μmol/L [2.1–3.0]) compared to those of group B1 (1.8 μmol/L [1.6–2.3]; p < 0.001) and healthy dogs (1.9 μmol/L [1.7–2.3]; p = 0.02). Median SDMA was significantly increased in dogs of group C+D (0.7 μmol/L [0.5–0.9]) compared to those of groups B1 (0.4 μmol/L [0.3–0.5]; p < 0.001), B2 (0.4 μmol/L [0.3–0.6]; p < 0.01), and the control group (0.4 μmol/L [0.35–0.45]; p = 0.001). In the final multivariable analysis, ADMA and SDMA were significantly associated with left atrium to aorta ratio (p < 0.001), and creatinine (p < 0.001), respectively. Increased plasmatic concentrations of dimethylarginines suggest a possible role as biomarkers of disease severity in dogs with decompensated MMVD.

Prognostic Value of Urinary and Plasma C-Type Natriuretic Peptide in Acute Decompensated Heart Failure

OBJECTIVES

This study sought to characterize urinary and plasma C-type natriuretic peptide (CNP) in acute decompensated heart failure (ADHF) to define their relationship with clinical variables and to determine whether urinary and plasma CNP together add prognostic value.

BACKGROUND

CNP is a protective hormone that is synthesized in the kidney and endothelium and possesses antiremodeling properties. Urinary and plasma CNP levels are elevated in pathophysiological conditions; however, their regulation and prognostic value in heart failure (HF) is unclear.

METHODS

Urinary and plasma CNP were measured in 109 healthy subjects and 208 patients with ADHF; the 95th percentile of CNP values from healthy subjects established the normal contemporary cutoffs. Patients with ADHF were stratified based on urinary and plasma CNP levels for clinical characterization and the assessment of risk for adverse outcomes.

RESULTS

There was no significant correlation between urinary and plasma CNP in both cohorts. Urinary and plasma CNP were significantly elevated in patients with ADHF, and both increased with disease severity and were positively correlated with plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP). Of the patients with ADHF, 23% had elevations in both urinary and plasma CNP, whereas 24% had normal CNP levels. During a median follow-up of 3 years, patients with elevated urinary and plasma CNP had a significantly higher risk of rehospitalization and/or death (HR: 1.79; P = 0.03) and rehospitalization (HR: 2.16; P = 0.01) after adjusting for age, sex, left ventricular ejection fraction, renal function, and plasma NT-proBNP. The C-statistic and integrated discrimination analyses further supported that the addition of urinary and plasma CNP to established risk models improved the prediction of adverse outcomes in patients with ADHF.

CONCLUSIONS

Urinary and plasma CNP are differentially regulated in ADHF, and elevations in both provided independent prognostic value for predicting adverse outcomes.

Urinary N-terminal pro-B-type natriuretic peptide as a biomarker for cardiovascular events in a general Japanese population: the Hisayama Study

BACKGROUND

Epidemiological evidence has shown that serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations, a diagnostic biomarker for heart failure, are positively associated with cardiovascular risk. Since NT-proBNP in serum is excreted in urine, it is hypothesized that urinary NT-proBNP concentrations are correlated with serum concentrations and linked with cardiovascular risk in the general population.

METHODS

A total of 3060 community-dwelling residents aged ≥ 40 years without history of cardiovascular disease (CVD) were followed up for a median of 8.3 years (2007-2015). Serum and urinary concentrations of NT-proBNP at baseline were compared. The hazard ratios (HRs) and their 95% confidence intervals (CIs) for the association between NT-proBNP concentrations and the risk of developing CVD were computed using the Cox proportional hazards model.

RESULTS

The median values (interquartile ranges) of serum and urinary NT-proBNP concentrations at baseline were 56 (32-104) pg/mL and 20 (18-25) pg/mL, respectively. There was a strong quadratic correlation between the serum and urinary concentrations of NT-proBNP (coefficient of determination [R²] = 0.72): urinary concentrations of 20, 27, and 43 pg/mL were equivalent to serum concentrations of 55, 125, and 300 pg/mL, respectively. During the follow-up period, 170 subjects developed CVD. The age- and sex-adjusted risk of CVD increased significantly with higher urinary NT-proBNP levels (P for trend < 0.001). This association remained significant after adjustment for traditional cardiovascular risk factors (P for trend = 0.009). The multivariable-adjusted risk of developing CVD almost doubled in subjects with urinary NT-proBNP of ≥ 43 pg/mL as compared to those with urinary NT-proBNP of ≤ 19 pg/mL (HR 2.07, 95% CI 1.20-3.56).

CONCLUSIONS

The present study demonstrated that urinary NT-proBNP concentrations were well-correlated with serum concentrations and were positively associated with cardiovascular risk. Given that urine sampling is noninvasive and does not require specially trained personnel, urinary NT-proBNP concentrations have the potential to be an easy and useful biomarker for detecting people at higher cardiovascular risk.

Associations of blood biomarkers with glomerular filtration rate in patients with TIA and stroke: population-based study

Background and purpose

Non-traditional risk factors such as chronic inflammation, oxidative stress and thrombogenic factors are believed to contribute to the excess stroke risk in chronic kidney disease (CKD) by triggering vascular injury and endothelial dysfunction. We aimed to determine how well a panel of biomarkers representative of these factors would correlate with estimated glomerular filtration rate (eGFR) in patients with recent transient ischaemic attack (TIA) or stroke. We also investigated whether eGFR would confound previously reported associations between biomarkers and mortality.

Methods

We studied a panel of 16 blood biomarkers related to inflammation, thrombosis, atherogenesis and cardiac or neuronal cell damage in TIA or ischaemic stroke in a population-based study (Oxford Vascular Study). Biomarker levels were log-transformed and correlated with eGFR, adjusted for age. Cox proportional hazard models were used for survival analysis.

Results

Among 1297 patients with TIA or stroke, 52.7% (n=684) of patients had CKD (eGFR <60 mL/min/1.73 m²). There was a moderate correlation between log-eGFR and the log-transformed soluble tumour necrosis factor receptor-1 (R²=0.21), attenuating with adjustment for age (R²=0.12). There were moderate-to-strong correlations with markers of cardiac injury, N-terminal pro-brain natriuretic peptide and heart-type fatty acid binding protein (hFABP, R²=0.14 and 0.34, respectively). The strongest correlation after adjustment for age was between hFABP and eGFR (R²=0.20). Adjusting for eGFR did not impact any biomarker associations with mortality.

Conclusions

Correlations between biomarkers related to inflammation and thrombosis with renal dysfunction in the setting of cerebrovascular events were generally modest after adjustment for age, suggesting that putative risk factors such as chronic inflammation or coagulopathy are unlikely to be important stroke mechanisms in patients with CKD.

Racial differences in the association of NT-proBNP with risk of incident heart failure in REGARDS

BACKGROUND

Black individuals have lower natriuretic peptide levels and greater risk of heart failure (HF) than white individuals. Higher N-terminal-pro-B-type natriuretic peptide (NT-proBNP) is associated with increased risk of incident HF, but little information is available in black individuals. We examined race-specific differences in 1) the association of NT-proBNP with incident HF and 2) the predictive ability of NT-proBNP for incident HF across body mass index (BMI) and estimated glomerular filtration rate (eGFR) categories.

METHODS

In a prospective case-cohort study, baseline NT-proBNP was measured among 687 participants with incident HF and 2,923 (weighted 20,075) non-case randomly selected participants. Multivariable Cox proportional hazard modeling was used to assess the objectives of our study. Global Wald Chi-square score estimated from multivariable Cox models was used to assess predictive ability of NT-proBNP across BMI and eGFR categories.

RESULTS

In the multivariable model, a doubling of NT-proBNP concentration was associated with greater risk of incident HF among white individuals [hazard ratio (HR): 1.73; 95% CI: 1.55-1.94] than black individuals (HR: 1.51; 95% CI: 1.34-1.70); Pinteraction by race = 0.024. Higher NT-proBNP was the strongest predictor of incident HF across all BMI and eGFR categories among white individuals. By contrast, among black individuals with obesity (BMI ≥ 30 kg/m2) or eGFR < 60 mL/min/1.73 m2, the predictive ability of NT-proBNP for incident HF was attenuated.

CONCLUSIONS

The magnitude of the association of higher NT-proBNP with incident HF risk was greater among white individuals than black individuals. The diminished ability of NT-proBNP to predict the risk of HF in black population with obesity or impaired kidney function highlights the need of further investigations.

Race-based demographic, anthropometric and clinical correlates of N-terminal-pro B-type natriuretic peptide

BACKGROUND

Population studies have shown that black race is a natriuretic peptide (NP) deficiency state. We sought to assess whether the effects of age, sex, body mass index (BMI) and estimated glomerular filtration rate (eGFR) on N-terminal-pro-B-type NP (NT-proBNP) levels differ in white and black individuals.

METHODS

The study population consisted of a stratified random cohort from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. The study outcomes were the effects of age, sex, BMI and eGFR on NT-proBNP levels independent of socioeconomic and cardiovascular disease factors. Multivariable regression analyses were used to assess the effects of age, sex, BMI and eGFR on NT-proBNP levels in blacks and whites.

RESULTS

Of the 27,679 participants in the weighted sample, 54.7% were females, 40.6% were black, and the median age was 64 years. Every 10-year higher age was associated with 38% [95% confidence interval (CI): 30%-45%] and 34% (95% CI: 22%-43%) higher NT-proBNP levels in whites and blacks, respectively. Female sex was associated with 31% (95% CI: 20%-43%) higher NT-proBNP levels in whites and 28% (95% CI: 15%-45%) higher in blacks. There was a significant linear inverse relationship between BMI and NT-proBNP in whites and a non-linear inverse relationship in blacks. Whites and blacks had a non-linear inverse relationship between eGFR and NT-proBNP. However, the non-linear relationship between NT-proBNP and eGFR differed by race (p = 0.01 for interaction).

CONCLUSIONS

The association of age and sex with NT-proBNP levels was similar in blacks and whites but the form of the BMI and eGFR relationship differed by race.

Performance analysis of AL amyloidosis cardiac biomarker staging systems with special focus on renal failure and atrial arrhythmia

Systemic light chain amyloidosis is a rare and life-threatening disorder, for which accurate risk stratification is crucial. Current cardiac staging systems (MAYO2004, MAYO3b, and MAYO2012) are mainly based on biomarkers, which have uncertain reliability in the context of atrial fibrillation, arrhythmia or pacemaker stimulation as well as renal insufficiency. We compared the performance of the established staging systems with particular regard to these comorbidities in 1,224 patients with systemic light chain amyloidosis diagnosed at our center from July 2002 until March 2017. We first characterized the subsets with an estimated glomerular filtration rate <50 mL/min/1.73 m² (415 patients) and any kind of atrial arrhythmia (183 patients) as unique high-risk subgroups with similarly increased cardiac biomarkers (χ²-test, all P<0.001). This resulted in a shift towards higher risk stages and reduced median overall survival compared to those of patients with better kidney function or without atrial arrhythmia in univariate analyses (13 vs. 46 months and 17 vs. 53 months, respectively; both P<0.001). Performance analysis revealed that predictions in the entire cohort were least precise with the MAYO2004 staging system and most precise with the MAYO3b system. This performance pattern was almost preserved for patients with an estimated glomerular filtration rate <50 mL/min/1.73 m², but less so for those with atrial arrhythmias. The MAYO3b staging system was most robust. Importantly, atrial arrhythmia retained its prognostic value in multivariable analysis including age, difference between involved and uninvolved free light chains, and any staging system, while estimated glomerular filtration rate <50 mL/min/1.73 m² was not statistically significant in multivariable analysis with the MAYO3b staging system. In conclusion, our results favor the MAYO3b staging system due to its consistently best performance and retained applicability in the subgroups with atrial arrhythmia and estimated glomerular filtration rate <50 mL/min/1.73 m².

Comparison of multiple biomarkers for mortality prediction in patients with acute heart failure of ischemic and nonischemic etiology

Aim: To investigate the prognosis of soluble ST2 (sST2), galectin-3 and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for death related to ischemic and nonischemic etiology of acute heart failure (HF). Methods: The associations between biomarkers and death were determined in 1020 patients admitted to hospital with acute HF. Results: During 1-year follow-up, 162 patients died. Multivariable regression analysis showed that the hazard ratios of sST2 and NT-proBNP for 1-year all-cause death was similar and remained significant between ischemic and nonischemic HF patients. However, galectin-3 was not significantly associated with death when sST2 and NT-proBNP were incorporated into model in ischemic HF patients. Conclusion: There is no etiology dependent prognostic ability of NT-proBNP or ST2 in patients with acute HF, but for galectin-3 there is no added prognostic ability in ischemic HF.

Exploring the relation between changes in NT-proBNP and renal function in patients with suspected heart failure using structural equation modelling

BACKGROUND

The relation between changes in NT-proBNP and renal function has commonly been studied using multiple regressions, which may ignore the complexity of relations between related variables.

METHODS AND RESULTS

Data were collected from patients referred with suspected heart failure (HF) to a community service. Structural equation modelling (SEM) was used to assess the association between changes in NT-proBNP at 1year, and other pre-specified variables including age, sex, BMI, eGFR, loop diuretics and ACE inhibitor. Of 1006 patients with a follow-up NT-proBNP at 1year, 882 (88%) had HF. The baseline median age was 72 (IQR: 63-78) years, 732 (73%) were men, 668 (66%) had left ventricular systolic dysfunction and 769 (76%) had NT-proBNP>400pg/ml. For all patients at 1year, 243 (24%) patients had at least a 50% reduction in NT-proBNP, and 199 (20%) had at least a 50% increase, only 40 (3%) had <3% change. Change in NT-proBNP was strongly associated with baseline NT-proBNP (the standardized coefficient (r)=0.73, p<0.001). The change in NT-proBNP was not associated with changes in eGFR, and was indirectly related with age, BMI, eGFR and loop diuretics (p<0.01 for all).

CONCLUSIONS

Baseline NT-proBNP was the main determinant of change in NT-proBNP at one year.

Cardiac Troponin I and Amino-Terminal Pro B-Type Natriuretic Peptide in Dogs With Stable Chronic Kidney Disease

Background

Increased concentrations of N‐terminal pro B‐type natriuretic peptide (NT‐proBNP) and cardiac troponin I (cTnI) in dogs with azotemia have been documented. Knowledge of mechanisms behind increased concentrations of cardiac biomarkers in dogs with azotemia is warranted for correct interpretation of test results.

Objectives

The aim of the article was to investigate possible associations between plasma concentrations of cTnI and NT‐proBNP, respectively, and patient characteristics, glomerular filtration rate (GFR), a plasma volume factor (PVF) derived from scintigraphic examination (PVf), systolic blood pressure (SBP), selected hematologic and biochemical variables, and echocardiographic measurements in dogs with stable chronic kidney disease (CKD) and in healthy dogs.

Animals

Fifty student‐, staff‐, and client‐owned dogs were included. Twenty‐three of the dogs were healthy and 27 were diagnosed with CKD.

Methods

In this cross‐sectional observational study, dogs with a previous diagnosis of CKD and healthy control dogs were included. At inclusion, all dogs were characterized by physical examination, repeated blood pressure measurements, complete urinalysis, hematology and biochemistry panel, echocardiography, abdominal ultrasound examination of the entire urinary tract, and scintigraphic examination for measurement of GFR.

Results

Plasma volume factor and PCV were independently associated with NT‐proBNP (Radj2 = 0.42; P < .0001). Age, body weight (BW), and SBP were independently associated with cTnI (Radj2 = 0.50; P < .0001).

Conclusions and Clinical Importance

Neither NT‐proBNP nor cTnI concentrations were independently associated with measured GFR. Thus, findings were not suggestive of passive accumulation of either marker, suggesting that increased circulating concentrations of cTnI and NT‐proBNP can be interpreted similarly in dogs with stable CKD as in dogs without CKD.

Improving the diagnostic accuracy of acute myocardial infarction with the use of high-sensitive cardiac troponin T in different chronic kidney disease stages

High-sensitive cardiac troponin T (hs-TnT) is a critical biomarker in diagnosis of acute myocardial infarction (AMI). However, CKD individuals usually have elevated hs-TnT even in the absence of AMI. Our study aimed to explore the optimal cutoff-value of hs-TnT and further to improve diagnostic accuracy of AMI in CKD patients. Clinical data of 489 patients were collected from the maintained database between September 2010 and June 2014. CKD patients with AMI were assigned to CKD+AMI group and CKD patients without AMI were assigned to CKD group. Receiver operating characteristic curves were utilized to derive the optimal cutoff-value. In CKD+STEMI and CKD group, hs-TnT was increased with descending eGFR. In CKD+NSTEMI group, hs-TnT showed an upward trend with increasing SYNTAX Score. In patients with CKD+STEMI, hs-TnT was significantly correlated with SYNTAX Score in CKD stage 2, stage 4 and in total. In CKD patients, the optimal cutoff-value of hs-TnT for diagnosis of AMI was 129.45 ng/l with 75.2% sensitivity and 83.2% specificity. The cutoff-value appeared to be hs-TnT level of 99.55ng/l in CKD stage 3, 129.45 ng/l in CKD stage 4, 105.50 ng/l in CKD stage 5 and 149.35 ng/l in dialysis patients, respectively. In different stages of CKD, eGFR-range-specific optimal cutoff-values should be considered.

Biomarkers of Cardiovascular Disease and Mortality Risk in Patients with Advanced CKD

BACKGROUND AND OBJECTIVES

The high risk of cardiovascular disease (CVD) and premature death in patients with CKD associates with a plethora of elevated circulating biomarkers that may reflect distinct signaling pathways or simply, are epiphenomena of CKD. We compared the predictive strength of 12 biomarkers analyzed concomitantly in patients with stage 5 CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

From 1994 to 2014, 543 patients with stage 5 CKD (median age =56 years old; 63% men; 199 patients had CVD) took part in our study on malnutrition, inflammation, and CVD in incident dialysis patients. Circulating levels of albumin, ferritin, high-sensitivity C-reactive protein (hsCRP), IGF-1, IL-6, orosomucoid, troponin T (TnT), TNF, soluble intracellular adhesion molecule, soluble vascular cellular adhesion molecule 1 (sVCAM-1), and platelet and white blood cell (WBC) counts were analyzed as predictors of the presence of clinically overt CVD at baseline, protein-energy wasting (PEW), and subsequent all-cause mortality. During follow-up for a median of 28 months, there were 149 deaths, 81 of which were caused by CVD.

RESULTS

Most biomarkers were elevated compared with reference values and--except for albumin, ferritin, and IGF-1-higher in patients with CVD. In receiver operating characteristic analysis, age, IL-6, TnT, hsCRP, and IGF-1 were classifiers of baseline CVD and predictors of all-cause mortality. In addition to age, diabetes mellitus, smoking (for CVD), and PEW, only IL-6, relative risk (RR) 1.10 and 95% confidence interval ([95% CI], 1.02 to 1.19), sVCAM-1 RR 1.09 (95% CI, 1.01 to 1.17), and serum albumin RR 0.89 (95% CI, 0.83 to 0.95) associated with baseline CVD, and only WBC, hazard ratio (HR) 1.94 (95% CI, 1.34 to 2.82), IL-6 HR 1.79 (95% CI, 1.20 to 2.67), and TNF HR 0.65 (95% CI, 0.44 to 0.97) predicted all-cause mortality.

CONCLUSIONS

In addition to age and comorbidities, only IL-6, sVCAM-1, and albumin could-independently of other biomarkers-classify clinical CVD, and only IL-6, WBC, and TNF could-independently of other biomarkers-predict all-cause mortality risk. These data underscore the robustness of IL-6 as a classifier of clinically overt CVD and predictor of all-cause mortality in patients with stage 5 CKD.

Soluble ST2 serum concentration and renal function in heart failure

BACKGROUND

Soluble ST2 (sST2) provides important prognostic information in patients with heart failure (HF). How sST2 serum concentration is related to renal function is uncertain. We evaluated the association between sST2 and renal function and compared its prognostic value in HF patients with renal insufficiency.

METHODS AND RESULTS

Patients (n = 879; median age 70.4 years; 71.8% men) were divided into 3 subgroups according to estimated glomerular filtration rate (eGFR): ≥60 mL/min/1.73 m(2) (n = 337); 30-59 mL/min/1.73 m(2) (n = 352); and <30 mL/min/1.73 m(2) (n = 190). sST2 (rho = -0.16; P < .001), N-terminal pro-B-type natriuretic peptide (rho = -0.40; P < .001), and high-sensitivity cardiac troponin T (rho = -0.47; P < .001) inversely correlated with eGFR. All-cause mortality was the primary end point. During a median follow-up of 3.46 years, 312 patients (35%) died, 246 of them from the subgroup of 542 patients with eGFR <60 mL/min/1.73 m(2) (45%). Biomarker combination including sST2 showed best discrimination, calibration, and reclassification metrics in renal insufficiency patients (net reclassification improvement 16.6 [95% confidence interval (CI) 8.1-25; P < .001]; integrated discrimination improvement 4.2 [95% CI 2.2-6.2; P < .001]). Improvement in reclassification was higher in these patients than in the total cohort.

CONCLUSIONS

The prognostic value of sST2 was not influenced by renal function. On top of other biomarkers, sST2 improved long-term prediction in patients with renal insufficiency even more than in the total cohort.

Serum B-type natriuretic peptide in the initial workup of patients with new onset ascites: a diagnostic accuracy study

Heart failure (HF) is, after cirrhosis, the second-most common cause of ascites. Serum B-type natriuretic peptide (BNP) plays an important role in the diagnosis of HF. Therefore, we hypothesized that BNP would be useful in the differential diagnosis of ascites. Consecutive patients with new onset ascites were prospectively enrolled in this cross-sectional study. All patients had measurements of serum-ascites albumin gradient (SAAG), total protein concentration in ascitic fluid, serum, and ascites BNP. We enrolled 218 consecutive patients with ascites resulting from HF (n = 44), cirrhosis (n = 162), peritoneal disease (n = 10), and constrictive pericarditis (n = 2). Compared to SAAG and/or total protein concentration in ascites, the test that best discriminated HF-related ascites from other causes of ascites was serum BNP. A cutoff of >364 pg/mL (sensitivity 98%, specificity 99%, and diagnostic accuracy 99%) had the highest positive likelihood ratio (168.1); that is, it was the best to rule in HF-related ascites. Conversely, a cutoff ≤ 182 pg/mL had the lowest negative likelihood ratio (0.0) and was the best to rule out HF-related ascites. These findings were confirmed in a 60-patient validation cohort.

CONCLUSIONS

Serum BNP is more accurate than ascites analyses in the diagnosis of HF-related ascites. The workup of patients with new onset ascites could be streamlined by obtaining serum BNP as an initial test and could forego the need for diagnostic paracentesis, particularly in cases where the cause of ascites is uncertain and/or could be the result of HF.

[Prognostic role of NT-proBNP in emergency department in the elderly with acute heart failure]

OBJECTIVE

To determine prognostic role of NT-proBNP as predictor of 30 day-mortality and readmission in the elderly with acute heart failure (AHF) treated in Spanish Emergency Departments (EDs), and to analyse the confounding factors when the NT-proBNP value is interpreted.

MATERIAL AND METHODS

A multicentre and multi-purpose cohort study with prospective follow-up was conducted on all patients aged 65 years or older with AHF treated in Spanish EDs. The variables recorded include demographic characteristics, comorbidity, details of episode, and NT-proBNP value. The outcome variables were 30 day-mortality and readmission. An NT-proBNP ≥ 5,180 pg/ml was adopted as the cut-off limit. The statistical package SPSS 18.0 was used to analyse the data.

RESULTS

A total of 585 patients were included, with a mean age of 80.4 (SD: 6.9) years old. The cut-off NT-proBNP ≥ 5,180 pg/ml was independently associated with a severely impaired glomerular filtration (<30 ml/h) (P < .001) and severe episode (NYHA II-IV) (P = .012). The NT-proBNP area under curve (AUC) for 30 day-mortality was 0.71 (CI 95%: 0.63-0.77; P < .001) and for 30 day-readmission, was 0.50 (CI 95%: 0.45-0.56; P = .846). A multivariable analysis showed that the cut-off NT-proBNP ≥ 5,180 pg/ml was an independent factor associated with 30 day-mortality in the elderly with AHF attended in Spanish EDs.

CONCLUSIONS

The NT-proBNP value is associated with short-term mortality in the elderly with AHF attended in the EDs independently of the presence of confounding factors, such as the severity of the episode and glomerular filtration reduction, but not with 30 day-readmission.

Agreement of BNP and NT-proBNP and the influence of clinical and laboratory variables

OBJECTIVE

To correlate the serum levels of B type natriuretic peptide and the N-terminal fraction of the pro-B type natriuretic peptide, as well as to analyze the influence of age, obesity, renal failure, left ventricle ejection fraction, diastolic dysfunction, and anemia on serum levels of both markers.

METHODS

An observational study in which the agreement was compared between these markers in consecutive samples of 138 patients. For the correlation, Pearson's test was used, and p<0.05 was considered statistically significant.

RESULTS

A linear association was observed between the B type natriuretic peptide and N-terminal fraction of the pro-B type natriuretic peptide (r=0.907; p<0.001). When evaluating the categorized measurements as normal and altered, there was good agreement, with 90.6% of agreement classifications (p<0.001) in which altered values of the N-terminal fraction of the pro-B type natriuretic peptide and normal values of the B type natriuretic peptide represented 8.7% of the total; the opposite situation represented 1% of the total. Assessment of the influence of the clinical and laboratorial factors on the levels of natriuretic peptides showed that they rise according to age, but that they fall as the ejection fraction increases. Patients with anemia (p<0.001) or with renal failure (p=0.007) had higher values of both markers. There was no association between obesity and the B type natriuretic peptide.

CONCLUSION

There was satisfactory agreement between the B type natriuretic peptide and the N-terminal fraction of the pro-B type natriuretic peptide. Age, creatinine levels, and hemoglobin, as well as ventricular function, influence the serum levels of both natriuretic peptides.

Refinement in patient selection to reduce treatment-related mortality from autologous stem cell transplantation in amyloidosis

This study sought to develop selection guidelines to determine the eligibility for SCT of patients with light-chain amyloidosis. Patients with biopsy-confirmed lightchain amyloidosis who underwent SCT between 8 March 1996 and 31 December 2011 were reviewed in two cohorts by date of transplantation: between 8 March 1996 and 30 June 2009 (n=410) and between 1 July 2009 and 31 December 2011 (n=89). Also evaluated were patients who died before post-transplant day 100 to determine the features predictive of early death. After 1 July 2009, fewer transplant recipients had Mayo stage III cardiac involvement. Mortality before post-transplant day 100 was 10.5% (43/410) in the earlier group and 1.1% (1/89) in the later group. In the earlier group, one-quarter of transplant recipients with N-terminal pro-brain natriuretic peptide (NT-proBNP) >5000 pg/mL died by 10.3 months. When serum troponin T was >0.06 ng/mL, 25% died at 3.7 months. The Mayo staging system is predictive for OS but not useful for selecting transplant recipients. Patients with serum troponin T >0.06 ng/mL or NT-proBNP >5000 pg/mL (not on dialysis) should not be considered candidates for SCT because of early mortality.

High-sensitive troponin T and N-terminal pro-B type natriuretic peptide are associated with cardiovascular events despite the cross-sectional association with albuminuria and glomerular filtration rate

AIMS

It has been suggested that troponins and natriuretic peptides can be falsely elevated in subjects with impaired kidney function because of decreased renal clearance. The value of these biomarkers in subjects with impaired kidney function has therefore been debated. We tested in a population-based cohort study, first, whether high-sensitive troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels are cross-sectionally associated with the estimated glomerular filtration rate (eGFR) and albuminuria, and secondly, whether these markers are associated with cardiovascular outcome, independent of eGFR, albuminuria and conventional cardiovascular risk factors.

METHODS AND RESULTS

We included 8121 subjects from the PREVEND study with both values of hsTnT and NT-pro-BNP available. High-sensitive troponin T >0.01 µg/L and NT-pro-BNP >125 ng/L were defined as elevated. We first performed linear regression analyses with hsTnT and NT-pro-BNP as dependent variables. Next, we performed Cox-regression analyses, studying the associations of hsTnT and NT-pro-BNP with incident cardiovascular events. Of our cohort, 6.7% had an elevated hsTnT and 12.2% an elevated NT-pro-BNP. Also, the estimated glomerular filtration rate, albuminuria, and ECG-assessed ischaemia and left ventricular hypertrophy were all significantly associated with hsTnT and NT-pro-BNP in the linear regression analyses. Both hsTnT and NT-pro-BNP appeared associated with cardiovascular events, and these associations remained significant after adjustment for eGFR, albuminuria, age, gender and conventional cardiovascular risk factors (P= 0.03 and P< 0.001, respectively). Only a few subjects with markedly reduced renal function were included. The results presented are therefore mainly valid for a population with mildly impaired renal function.

CONCLUSION

These data indicate that a finding of an increased hsTnT or NT-pro-BNP in subjects with chronic kidney disease stages 1/3 should be taken seriously as a prognostic marker for a worse cardiovascular outcome and not be discarded as merely a reflection of decreased renal clearance.